What Researchers Did
Researchers used ultrasound to measure cardiovascular function in 8 professional divers before and after a hyperbaric air exposure to 400 kPa (approximately 4 ATA) with extended oxygen breathing during decompression.
What They Found
After the dive, diastolic blood pressure increased, heart rate decreased significantly, and cardiac output dropped measurably. Carotid artery blood flow velocity decreased, while brachial artery diameter tended to increase. Changes were described as mild and not clinically alarming.
What This Means for Canadian Patients
For recreational and professional Canadian divers, this study confirms that hyperbaric air exposure causes measurable but mild cardiovascular changes. The extended oxygen breathing during decompression, used to prevent decompression sickness, appears to moderately affect heart function in the short term.
Canadian Relevance
No direct Canadian connection identified. Relevant to occupational diving safety in Canada marine and offshore industries.
Study Limitations
Only 8 divers were studied in a single controlled dive profile, severely limiting generalizability to real-world diving conditions.